Sophie Charlotte Elisabeth Weingarten was born on May 5, 1760, in Glatz, Lower Silesia, then part of the Kingdom of Prussia (modern-day Kłodzko, Poland). She was the daughter of the secretary of the Austrian legation, a man of some standing who later lost his position. Faced with reduced social and financial prospects, Sophie married Theodor Ursinus, a much older Privy Counsellor of the Supreme Court, at the age of 19. This strategic union allowed her to maintain her status within upper-class society despite her family's decline.

The couple lived in Stendal and later in Berlin, where they maintained an outwardly respectable lifestyle. However, their marriage was reportedly distant, and Sophie began a long-term extramarital relationship with a Dutch officer named Rogay. The relationship may have occurred with her husband’s knowledge or consent, a possibility given the cultural tolerance among the Prussian elite for discreet affairs.

After the death of her husband and later legal troubles, Sophie claimed her decline began after being exposed to alcohol and public office, and it is likely that social expectations, financial dependency, and personal ambition contributed to her criminal behavior. She enjoyed the comforts of high society, but following her trial, she spent decades in incarceration, only to return to social life again before her death.

Sophie Ursinus’s criminal behavior first came under scrutiny after the sudden death of her husband, Theodor Ursinus, in Berlin on September 11, 1800 — the day after his birthday celebration. His passing was suspicious not only for its abruptness but also for Sophie’s failure to summon a doctor when his condition worsened after she administered medicine. Although there was no autopsy at the time, and arsenic poisoning could not yet be scientifically confirmed, suspicions lingered.

In the years surrounding her husband's death, two other people close to her also died under questionable circumstances. First was her long-time lover, Rogay, a Dutch military officer who died around 1797. His death was attributed to tuberculosis, but it was later discovered that Sophie had purchased arsenic shortly before his demise — suggesting premeditation.

Then, on January 24, 1801, Sophie's aunt, Christiane Witte, died after a brief illness in Charlottenburg. Shortly before her death, Sophie again acquired a large quantity of arsenic. Witte’s passing was followed by the transfer of a considerable inheritance to Sophie, heightening suspicion.

The unraveling of Sophie’s crimes began not with a death, but with an attempted murder. In February 1803, her servant Benjamin Klein fell violently ill after a quarrel with her. Sophie gave him an emetic and then some soup, which only worsened his condition. Klein, suspicious of her intentions, had a batch of plums she offered him examined by a chemist. The results revealed they contained arsenic. This discovery triggered her arrest.

Authorities exhumed the bodies of both her husband and her aunt. Although the body of her husband showed no definitive forensic signs of arsenic due to limitations in chemical testing at the time, the examiners noted symptoms consistent with poisoning. In contrast, the autopsy of her aunt definitively confirmed arsenic poisoning. Chemist Valentin Rose and his mentor Martin Heinrich Klaproth were instrumental in identifying the signs of arsenic, helping establish a forensic precedent.

Sophie Ursinus was tried in 1803 and found guilty of the murder of her aunt and attempted murder of her servant. Her role in her husband’s death was not definitively proven, although suspicion remained. The trial concluded on September 12, 1803, and she was sentenced to life imprisonment.

Remarkably, Sophie did not suffer the harsh conditions typically associated with life sentences. Held in Glatz prison, she was allowed to wear fine clothing and even host guests — a reflection of her lingering societal status. In 1833, after serving 30 years, she was pardoned and released, rejoining upper-class society in Glatz. She lived out her final years in relative comfort and died on April 4, 1836, at the age of 75.